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The application of in situ Raman spectroscopy under multiple fields is widely recognized as an effective approach for investigating the physical mechanism of phase transitions in ferroelectrics, because it can directly provide the detailed information about the vibration evolution of various phonon modes within lattices, such as bond stretching and rotation. Based on this technique, our work aims to thoroughly probe the dynamics of phase transitions in traditional ferroelectric potassium sodium niobate [(K,Na)NbO3, KNN] under external fields, by analyzing the in situ dependence of wavenumber and intensity of phonon modes under the varying temperature and electric fields. The results indicate that different vibration modes respectively relating to the A-site ions and NbO6 octahedra in KNN exhibit distinct and abrupt distortion behavior during the orthorhombic-tetragonal and tetragonal-cubic transitions. Moreover, a certain degree of distortion can still be observed in the cubic phase above the Curie temperature. With an applied electric field, KNN presents quite different electrostriction in orthorhombic and tetragonal phases. Particularly, more than one kind of phonon mode undergoes non-linear variations under the varying electric fields, accompanied by the mutations at some fixed fields. These findings will be conducive to further understanding the phase transition mechanism in KNN from the perspective of phonon evolution. Simultaneously, it will also give crucial guidance for the design and development of KNN-based ferroelectrics as well as functional devices. [ABSTRACT FROM AUTHOR]

This work aims to provide a thorough analysis of the phase transition dynamics in lead-free Bi0.5Na0.5TiO3 by in situ Raman spectroscopy, which is conducted under varying temperature and electric field. All the transition points are proved by the Raman response of phonon vibration, including the depolarization temperature at ∼200 °C, potential transition at ∼280 °C, Curie temperature at ∼320 °C and tetragonal-cubic transition above ∼500 °C. The vibration of A-site ions primarily contributes to the depolarization behavior, which is also responsible for the strong polarity in Bi0.5Na0.5TiO3. The transitions at ∼280 °C and ∼320 °C are confirmed by the phonon vibrations of the Ti–O bonds and the TiO6 octahedra. Meanwhile, the distortion of the Ti–O bonds and TiO6 octahedra under an electric field results in weak polarity. The thermal hysteresis behavior is related to the dynamics of phonon thermal evolution, because of the delayed response of the vibration mode to thermal activation of Ti–O bonds and TiO6 octahedra. The results lay a foundation for understanding the mechanism of the phase transition and polarization in Bi0.5Na0.5TiO3, guiding the design of functional devices for electromechanical applications. [ABSTRACT FROM AUTHOR]

The helical pitch formed by organic molecules, such as the α-helix of proteins, usually requires hydrogen bonding between chiral units and long-range positional order. It was recently found that certain liquid crystal oligomers can have a twist-bend nematic (NTB) phase with nanoscale heliconical structure without hydrogen bonding, molecular chirality or positional order. To understand the nature of this unique structure, here we present hard and resonant tender X-ray scattering studies of two novel sulfur containing dimer materials. We simultaneously measure the temperature dependences of the helical pitch and the correlation length of both the helical and positional order. In addition to an unexpected strong variation of the pitch with the length of the spacer connecting the monomer units, we find that at the transition to the NTB phase the positional correlation length drops. The helical structure was found not only in the NTB phase but observed even in the upper range of a smectic phase that forms just below the NTB state. The coexistence of smectic layering and the heliconical order indicates a layered (SmATB) phase wherein the rigid units of the dimers are tilted with respect to the smectic layer normal in order to accommodate the bent conformation of the dimers and the tilt direction rotates along the heliconical axis. [ABSTRACT FROM AUTHOR]

Cell adhesion plays a critical role in many cellular functions, such as the hemostatic/thrombotic process, inflammatory reactions, and adaptive immune response. Many cell adhesion processes involve crosstalk between multiple ligand–receptor systems through intracellular signaling. To elucidate such crosstalk requires analysis of the synergistic or antagonistic effects of binding and signalling of multi-receptor species. Current techniques for these analyses, e.g., atomic force microscopy (AFM) and biomembrane force probe (BFP) assays, are either labor-intensive, low-throughput, or limited in the types of ligands they can interrogate. Circumventing these limitations requires a technique for manipulating ligand interactions with and measuring the functional response of a population of cells. In this work, we have developed a microfluidic platform for studying the binding and signaling of multi-receptor species by separating their actions in space and time. The platform directs cells through a single channel and uses sequentially presented ligands for pre-processing and stimulating cells, followed by reporting of cell activation states and functional consequences. Our method precisely patterns multiple proteins in different spatial regions without gaps. We demonstrate the utility of our method by using this platform to analyze the crosstalk between platelet receptors, glycoprotein Ib and IIb–IIIa, in the context of platelet adhesion and signaling under flow. We show the clinical utility of this platform by applying it to analyze whole blood samples and to assess differences in the activation of platelets between healthy and diabetic patients. [ABSTRACT FROM AUTHOR]

Here we report a novel chiral smectic through self-assembling two-dimensional graphene oxide nanosheets and one-dimensional cellulose nanorods. As shown by a phase diagram, the formation of the chiral smectic strictly depends on the ratio of nanosheets to nanorods as well as the concentration of the composite colloid. It would open up a new way for the development of mesoscopic materials with tunable physical properties, such as optical metamaterials with application in optical modulation and mechanochromic sensors. [ABSTRACT FROM AUTHOR]

Herein, we report a one-pot approach to produce HMF from aquatic microalgae (Chlorococcum sp.) with a yield up to 48.0% under mild reaction conditions (200 °C, 2 h) over the commercial cheap H-ZSM-5 catalyst. Conversion of microalgae to HMF involved three steps: (1) degradation of microalgae to carbohydrates; (2) hydrolysis of polysaccharides to glucose and mannose; (3) their isomerization to fructose on Lewis acid sites and its further dehydration to HMF over Brønsted acid sites. Proteins and lipids in microalgal cells play an important role in stabilizing HMF in water. Ball-milling pretreatment or addition of another organic solvent enhanced the productivity of HMF from microalgae. Besides, this cheap H-ZSM-5 catalyst also demonstrated excellent stability, and a slight loss of its activity can be easily recovered by simple calcination treatment. [ABSTRACT FROM AUTHOR]

The catalytic valorization of microalgae, a sustainable feedstock to alleviate dependence on fossil fuel and offset greenhouse gases emissions, is of great significance for production of biofuels and value-added chemicals from aquatic plants. Here, an interesting catalytic process is reported to convert microalgae (Chlorococcum sp.) into 1,2-propanediol (1,2-PDO) and ethylene glycol (EG) in water over nickel-based catalysts. The influences of reaction temperature, initial H2 pressure and reaction time on the product distribution were systematically investigated by using a batch reactor. Under optimal reaction conditions (at 250 °C for 3 h with 6.0 MPa of H2 pressure), microalgae were directly and efficiently converted over a Ni–MgO–ZnO catalyst and the total yield of polyols was up to 41.5%. The excellent catalytic activity was attributed to the smaller size and better dispersion of Ni particles on the MgO–ZnO supporter based on the characterization results as well as its tolerance to nitrogen-containing compounds. Besides, the reaction pathway was proposed based on the formation of reaction intermediates and the results of model compound conversion. [ABSTRACT FROM AUTHOR]

Sonodynamic therapy (SDT) is gaining popularity in cancer treatment due to its superior controllability and high tissue permeability. Nonetheless, the efficacy of SDT is severely diminished by the transient generation of limited reactive oxygen species (ROS). Herein, we introduce an acid-activated nanosonosensitizer, CaO 2 @PCN, by the controllable coating of porphyrinic metal-organic frameworks (PCN-224) on CaO 2 to induce cascaded oxidative stress in tumors. The PCN-224 doping can generate ROS during SDT to induce intracellular oxidative stress and abnormal calcium channels. Meanwhile, the ultrasound also promotes extracellular calcium influx. In addition, CaO 2 @PCN sequentially degrades in the tumor cell lysosomes, releasing Ca 2+ and H 2 O 2 to induce further abnormal calcium channels and elevate the levels of Ca 2+ . Insufficient catalase (CAT) in tumor cells promotes intracellular calcium overload, which can induce persistent ROS generation and mitochondrial dysfunction through ion interference therapy (IIT). More importantly, PCN-224 also protects CaO 2 against significant degradation under neutral conditions. Hence, the well-designed CaO 2 @PCN produces synergistic SDT/IIT effects and persistent ROS against cancer. More notably, the acidity-responsive biodegradability endows CaO 2 @PCN with excellent biosafety and promising clinical potential.

A high-fat diet (HFD) is associated with various adverse health outcomes, including cognitive impairment and an elevated risk of neurodegenerative conditions. This relationship is partially attributed to the influence of an HFD on the gut microbiota. The objective of this research was to evaluate the neuroprotective benefits of co-fermented black barley and quinoa with Lactobacillus (FG) against cognitive impairments triggered by an HFD and to investigate the microbiota-gut-brain axis mechanisms involved. C57BL/6J mice were randomized into four groups: the normal control group (NC, n = 10), the high-fat diet group (HFD, n = 10), the high-fat diet group supplemented with FG (HFG, 10 mL per kg BW, n = 10), and the high-fat diet group supplemented with Lactobacillus (HFL, 10 mL per kg BW, n = 10). Our results showed that the FG intervention enhanced the behavioral and locomotor skills of the mice, elevated the levels of dopamine (DA) and norepinephrine (NPI) in brain tissues, and alleviated synaptic ultrastructural damage in the hippocampus. Furthermore, FG intervention was observed to exert a protective effect on both the blood-brain barrier and the colonic barrier, as evidenced by an increase in the mRNA levels of Zona occludens-1 ( ZO-1 ), Claudin-4 , and Occludin in the hippocampus and colon. These beneficial effects may be attributed to FG's regulation of gut microbiota dysbiosis, which involves the restoration of intestinal flora diversity, reduction of the Firmicutes / Bacteroidetes (F/B) ratio, and a decrease in the levels of pro-inflammatory bacteria such as s_Escherichia coli E and g_Escherichia ; moreover, there was an increase in the abundances of anti-inflammatory bacteria, such as s_Bacteroides thetaiotaomicron and s_Parabacteroides goldsteinii . Metagenomic analysis revealed that the FG treatment downregulated the lipopolysaccharide (LPS) pathway and upregulated neurotransmitter biosynthetic pathways. These probiotic effects of FG resulted in reduced production and "leakage" of LPS and decreased mRNA expression of Toll-like receptor 4 ( Tlr4 ), cluster of differentiation 14 ( CD14 ), and myeloid differentiation factor 88 ( Myd88 ) in hippocampal and colon tissues. Consequently, a reduction was observed in the levels of inflammatory cytokines in the serum, hippocampus, and colon, along with suppression of the immunoreactivity of microglia and astrocytes. Our results suggest that FG may serve as an intervention strategy for preventing cognitive impairments caused by an HFD.

Dielectric capacitors are widely used in the field of pulsed power systems owing to their ultra-fast charge and discharge capacity; however, considering the complex environment they face in practical applications, how to further improve their thermal stability is an urgent issue that needs to be solved. Tungsten bronzes have the potential to broaden the temperature stability range owing to their unique structure, but only few studies have focused on them. Herein, lead-free Sr 4- x La x Na 2 Hf x Nb 10- x O 30 ceramics with a tungsten bronze structure were synthesized, and their energy storage properties were comprehensively characterized. With proper Hf substitution in the B site and rare earth substitution in the A site, significantly enhanced relaxor behavior is induced, leading to a broad plateau of the dielectric curve, slim polarization-electric field loop, high energy storage efficiency and stable capacitive performance over a wide temperature range. In addition, an improved microstructure with fewer defects, decreased average grain size, increased band gap and resistance were obtained, which benefit to the increase in breakdown strength and energy storage density. Finally, improved energy storage performance and thermal stability were achieved for the compounds, with W total = 3.6 J cm -3 , W rec = 80% and stable temperature range = 20-160 °C. Thus, the current system is a promising candidate for application in temperature-stable dielectric capacitors.-3 , η = 80% and stable temperature range = 20-160 °C. Thus, the current system is a promising candidate for application in temperature-stable dielectric capacitors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The generation of pseudo-magnetic fields in strained graphene leads to quantized Landau levels in the absence of an external magnetic field, providing the potential to achieve a zero-magnetic-field analogue of the quantum Hall effect. Here, we report the realization of a pseudo-magnetic field in epitaxial graphene by building a monolayer CrCl 2 /graphene heterointerface. The CrCl 2 crystal structure exhibits spontaneous breaking of three-fold rotational symmetry, yielding an anisotropic displacement field at the interface. Using scanning tunneling spectroscopy, we have discovered a sequence of pseudo-Landau levels associated with massless Dirac fermions. A control experiment performed on the CrCl 2 /NbSe 2 interface confirms the origin as the pseudo-magnetic field in the graphene layer that strongly interacts with CrCl 2 . More interestingly, the strength of the pseudo-magnetic fields can be tuned by the twist angle between the monolayer CrCl 2 and graphene, with a variation of up to threefold, depending on the twist angle of 0° to 30°. This work presents a rare 2D heterojunction for exploring PMF-related physics, such as the valley Hall effect, with the advantage of easy and flexible implementation.

Due to the success of halide perovskites in the photovoltaic field, halide perovskite-derived semiconductors have also been widely studied for optoelectronic applications. However, the photovoltaic performance of these perovskite derivatives still lags significantly behind their perovskite counterparts, mainly due to deficiencies at the B-site or X-site of the derivatives, which disrupt the connectivity of the key [BX 6 ] octahedra units. Herein, we developed a class of antiperovskite-derived materials with the formula , achieved by splitting the A anion, originally at the corner site of the cubic antiperovskite structure, into three edge-centered sites. This structural transformation maintains the three-dimensional octahedral framework. The thermodynamic stability, dynamical stability, and band gaps of 80 compounds were calculated using first-principles calculations. Based on criteria including stability and electronic properties, we identified 9 promising antiperovskite derivatives for further evaluation of their photovoltaic performance. Notably, the calculated theoretical maximum efficiencies of Ba 3 BiI 3 , Ba 3 SbI 3 , and Ba 3 BiBr 3 all exceed 24.5%, which is comparable to that of CH 3 NH 3 PbI 3 solar cells. Interpretable machine learning analysis was further carried out to identify critical physical descriptors influencing thermodynamic stability and band gap. Our work provides a novel approach for designing high performance perovskite-type structure-inspired semiconductors with potential for optoelectronic applications.

CRISPR/Cas12a systems have been repurposed as powerful tools for developing next-generation molecular diagnostics due to their trans -cleavage ability. However, it was long considered that the CRISPR/Cas12a system could only recognize DNA targets. Herein, we systematically investigated the intrinsic trans -cleavage activity of the CRISPR/Cas12a system (LbCas12a) and found that it could be activated through fragmented ssDNA activators. Remarkably, we discovered that the single-stranded DNA (ssDNA) activators in the complementary crRNA-distal domain could be replaced by target miRNA sequences without the need for pre-amplification or specialized recognition mechanisms. Based on these findings, we proposed the "Fragment Complementary Activation Strategy" (FCAS) and designed reverse fluorescence-enhanced lateral flow test strips (rFLTS) for the direct detection of miRNA-10b, achieving a limit of detection (LOD) of 5.53 fM and quantifying the miRNA-10b biomarker in clinical serum samples from glioma patients. Moreover, for the first time, we have developed the FCAS-based CRISPR/Cas12a system for miRNA in situ imaging, effectively recognizing tumor cells. The FCAS not only broadens the scope of CRISPR/Cas12a system target identification but also unlocks the potential for in-depth studies of CRISPR technology in many diagnostic settings., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Here we developed a microdroplet-based strategy for the rapid synthesis of uniform polydopamine nano- and microspheres. Polydopamine spheres with controllable sizes were generated within hundreds of microseconds by simply spraying water solutions of dopamine into microdroplets. Mass spectrometry revealed that dopamine was primarily oxidized into aminochrome, acting as the major building block for polydopamine. We anticipate that microdroplet chemistry will be rich in opportunities for the synthesis of functional nano- and micromaterials.

Complexes featuring metal-metal bonds play crucial roles in catalysis and small molecule activation due to the synergistic effects between the metals. Here, we report a series of homometallic cobalt complexes with metal-metal interactions that have been successfully stabilized by a multidentate ligand platform. Theoretical studies on metal-metal interactions in these cobalt complexes are discussed.

Controllable transformation is a prerequisite to the in-depth understanding of structure evolution mechanisms and structure-property correlations at the atomic level. Most transformation cases direct the directional evolution of nanocluster sizes, i.e. , size-maintained, size-increased, or size-reduced transformation, while size disproportionation was rarely reported. Here, we report the Au-doping-induced size disproportionation of nanocluster transformation. Slight Au-doping on the bimetallic (AgCu) 43 nanocluster produced its trimetallic derivative, (AuAgCu) 43 , following a size-maintained transformation. By comparison, the (AgCu) 43 nanocluster underwent a size-disproportionation transformation under heavy Au alloying, leading to the formation of size-reduced (AuAgCu) 33 and size-increased (AuAgCu) 56 nanoclusters simultaneously. Such a size disproportionation among the nanocluster transformations was verified by the thin-layer chromatography analysis. This work presented a novel nanocluster transformation case with a size disproportionation characteristic, expected to provide guidance for the understanding of cluster size evolutions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The occurrence and progression of mild cognitive impairment (MCI) are closely related to dysbiosis of the gut microbiota. Ginsenoside compound K (CK), a bioactive component of ginseng, has been shown to alleviate gut microbiota dysbiosis and neural damage. However, the mechanisms by which CK regulates the gut microbiota to improve MCI remain unexplored. In this study, an MCI mouse model induced by D-galactose was used, and 16S rRNA gene sequencing, metabolomics, transcriptomics, and integrative multi-omics analyses were employed to investigate the potential mechanisms by which CK alleviates MCI through modulation of the gut microbiota. The results demonstrated that CK repaired intestinal barrier dysfunction caused by MCI, improved blood-brain barrier (BBB) integrity, inhibited activation of microglial cells and astrocytes, and significantly ameliorated MCI. Furthermore, CK enhanced gut microbiota diversity, notably enriched beneficial bacteria such as Akkermansia , and modulated the levels of short-chain fatty acids (SCFAs), particularly increasing propionate, thereby alleviating gut microbiota dysbiosis caused by MCI. Germ-free experiments confirmed that gut microbiota is a key factor for ginsenoside CK in relieving MCI. Further investigation revealed that CK regulated the TLR4-MyD88-NF-κB signaling pathway through modulation of gut microbiota-mediated propionate metabolism, significantly reducing systemic inflammation and alleviating MCI. Our findings provide a new theoretical basis for using CK as a potential means of modulating the gut microbiota for the treatment of MCI.

Developing high-efficiency electrocatalysts for nitrate-to-ammonia transformation holds significant promise for the production of ammonia, a crucial component in agricultural fertilizers and as a carbon-free energy carrier. In this study, we propose a viable strategy involving sulfur doping to modulate both the microstructure and electronic properties of CoSe 2 for nitrate reduction. This approach remarkably enhances the conversion of nitrate to ammonia by effectively regulating the adsorption capability of nitrogenous intermediates. Specifically, sulfur-doped CoSe 2 nanowires (S-CoSe 2 NWs) exhibit a peak faradaic efficiency of 93.1% at -0.6 V vs. RHE and achieve the highest NH 3 yield rate of 11.6 mg h -1 cm -2 . Mechanistic investigations reveal that sulfur doping facilitates the creation of highly charged active sites, which enhance the adsorption of nitrite and subsequent hydrogenation, leading to improved selectivity towards ammonia production.

Regulating the performance of peroxidase (POD)-like nanozymes is a prerequisite for achieving highly sensitive and accurate immunoassays. Inspired by natural enzyme catalysis, we design a highly active and selective nanozyme by loading atomically dispersed tungsten (W) sites on Pd metallene (W-O-Pdene) to construct an artificial three-dimensional (3D) catalytic center. The 3D asymmetric W-O-Pd atomic pairs can effectively stretch the O-O bonds in H 2 O 2 and further promote the desorption of H 2 O to enhance POD-like activity. Moreover, the W-O-Pd sites with unique spatial structures demonstrate satisfactory specificity for H 2 O 2 activation, effectively preventing the interference of dissolved oxygen. Accordingly, the highly active and specific W-O-Pdene nanozymes are utilized for sensitive and accurate prostate-specific antigen (PSA) immunoassay with a low detection limit of 1.92 pg mL -1 , superior to commercial enzyme-linked immunosorbent assay., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A functionalized modified metal-organic framework material, T-MOF-808, was synthesized through hydrophobic modification with tetraethyl orthosilicate (TEOS) and chlorotrimethylsilane (TMCS). Then a supported oxidative desulfurization catalyst, [C 12 Py] 3 (NH 4 ) 3 Mo 7 O 24 /T-MOF-808(s), was prepared by using a heteropoly acid ionic liquid as the active component. The prepared samples were characterized using FT-IR, XRD, SEM, TEM, XPS, etc . [C 12 Py] 3 (NH 4 ) 3 Mo 7 O 24 /T-MOF-808(s) was used in the oxidative desulfurization of dibenzothiophene (DBT). At the same time, the effects of different loadings of the active component, oxygen sulfur ratios, reaction temperatures, and reaction time were also investigated. [C 12 Py] 3 (NH 4 ) 3 Mo 7 O 24 /T-MOF-808-15%(s) could oxidize 100% of DBT in 40 min at 60 °C. Significantly, the catalyst exhibited no discernible decline in catalytic activity after 14 runs. In addition, the efficiency of sulfur removal was 85.76% in actual diesel oil. It was found that the cooperative impact of hydrophobic modification and electron transfer makes an important contribution to the high activity. The hydrophobic modification provides a novel approach for using MOF materials in the oxidative desulfurization process.

The excited-state proton transfer (ESPT) reaction between anthracen-2-yl-3-phenylurea (PUA) derivatives and tetrabutylammonium acetate (TBAAc) in dimethyl sulfoxide (DMSO) solvent was theoretically investigated using time-dependent density functional theory. The electron-donating methoxy group (OMe) and electron-withdrawing trifluoromethyl group (CF 3 ) were bonded to 2PUA to form OMe-2PUA and CF 3 -2PUA, respectively. Two hydrogen bonds formed in the 1 : 1 hydrogen-bonded complexes between the 2PUA derivative and acetate ion (AcO - ), namely N1-H1⋯O1 and N2-H2⋯O2. Strong charge transfer (CT) due to the electron-donating OMe group led to H1 transfer in the S 1 state for the OMe-2PUA:AcO - hydrogen-bonded complex. On the contrary, weak CT due to the electron-withdrawing CF 3 group led to H2 transfer in the S 1 state for CF 3 -2PUA. After the ESPT reaction, the binding energies of the hydrogen-bonded complexes strongly decreased in both cases, and this promoted the separation of contact-ion pairs (CIPs*) and formed different types of anionic species. CF 3 -2PUA - could keep its nearly planar structure in the S 1 state and emit "abnormal" fluorescence. On the other hand, the anionic OMe-2PUA - underwent a twisting motion to form a twisted structure in the S 1 state with very low energy, and this led to a rapid internal conversion (IC) to quench long-wave fluorescence in the emission spectra.

Here we present a hybrid catalytic pathway for efficient synthesis of 5-aminomethyl-2-furancarboxylic acid (AMFC), a bio-based nylon-6 analogue monomer, from 5-hydroxymethylfurfural (HMF). This method combines homogeneous-catalyzed selective oxidation of HMF to 5-formyl-2-furancarboxylic acid (FFCA) with heterogeneous-catalyzed reductive amination using ammonia as the nitrogen source. Through this relay strategy, we achieve significant enhancements in overall efficiency, resulting in isolation yields of up to 92% for highly selective and scalable AMFC production from HMF.

Selective activation of the benzylic C(sp 3 )-H bond is pivotal for the construction of complex organic frameworks. Achieving precise selectivity among C-H bonds with comparable energetic and steric profiles remains a profound synthetic challenge. Herein, we unveil a site- and stereoselective benzylic C(sp 3 )-H alkenylation utilizing metallaphotoredox catalysis. Various linear and cyclic ( Z )-all-carbon tri- and tetrasubstituted olefins can be smoothly obtained. This strategy can be applied to complex substrates with multiple benzylic sites, previously deemed unsuitable due to the uncontrollable site-selectivity. In addition, sensitive functional groups such as terminal alkenyl and TMS groups are compatible under the mild conditions. The exceptional site-selectivity and broad substrate compatibility are attributed to the visible-light catalyzed relay electron transfer-proton transfer process. More importantly, we have extended this methodology to achieve enantioselective benzylic C(sp 3 )-H alkenylation, producing highly enantioenriched products. The applicability and scalability of our protocol are further validated through late-stage functionalization of complex structures and gram-scale operations, underscoring its practicality and robustness., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The poor reversibility of the zinc (Zn) anodes and the irreversible deposition/dissolution of Mn 2+ /MnO 2 significantly impede the commercialization of Zn-Mn aqueous batteries (ZMABs). In reducing the difference between the desired interfacial reaction environments of the cathode and anode, we found that they face the same problem of interference-the generation of irreversible corrosion products. Herein, we have introduced a novel self-regulatory mechanism. This mechanism involves the addition of sodium dihydrogen phosphate, which shifts from passive protection to active regulation. It effectively captures OH - ions, prevents corrosion product formation, and facilitates the in situ generation of a solid electrolyte interface (SEI) film. This modification also homogenizes Zn ion flow and improves the reversibility of Zn plating and stripping. Furthermore, a stable and slightly acidic environment has been established to stabilize the pH at the cathodic interface, mitigate corrosion product formation, and enhance the reversible deposition and dissolution of Mn 2+ /MnO 2 . With the optimal electrolyte, Zn‖Zn symmetric cells demonstrate stable operation for over 3000 hours at 1 mA cm -2 , 1 mA h cm -2 . Additionally, the Zn‖Cu cells maintain high reversibility after 1000 cycles, achieving an average coulombic efficiency (CE) of 99.76%. The assembled Zn‖MnO 2 full cells exhibit exceptional cycling stability and rate performance. This work adopts the approach of seeking common ground and emphasizing the balance of cathode and anode interfacial requirements, which represents a new and significant insight for design of ZMABs with high reversibility and high cyclability., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Perfluoro-1-butanesulfonic acid (PFBS) was used to etch on the surface of a zinc anode to introduce a 3D C 4 F 9 O 3 S-Zn interface layer with unique fluorine groups (Zn@PFBS) to inhibit the formation of dendrites. The C-F chains in the Zn@PFBS coating enhance the anode hydrophobicity of the zinc metal, which not only suppresses the HER of the surface of the zinc metal, but also strengthens the corrosion resistance of the zinc metal. Meanwhile, -SO 3 - in the coating enhanced the binding energy with Zn 2+ , which acted as a nucleation site on the surface of the zinc anode to induce the uniform deposition of Zn 2+ and inhibited the disordered growth of zinc dendrites. As a result, the symmetric battery assembled with the Zn@PFBS anode achieved a stable cycling of 6200 cycles at 5 mA cm -2 to 1 mA h cm -2 . Meanwhile, the Zn@PFBS anode exhibited a higher cycling performance with a capacity retention rate of 78.6% after 1000 cycles in a Zn@PFBS//Na 5 V 12 O 32 (NVO) full cell., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The intricate correlation between lattice geometry, topological behavior and charge degrees of freedom plays a key role in determining the physical and chemical properties of a quantum-magnetic system. Herein, we investigate the introduction of the unusual oxidation state as an alternative pathway to modulate the magnetic ground state in the well-known S = 1 Haldane system nickelate Y 2 BaNiO 5 (YBNO). YBNO is topologically reduced to incorporate d 9 -Ni + ( S = 1/2) in the one-dimensional Haldane chain system. The random distribution of Ni + for the first time results in the emergence of a one-dimensional ferromagnetic phase with a transition temperature far above room temperature. Theoretical calculations reveal that the antiferromagnetic interplay can evolve into ferromagnetic interactions with the presence of oxygen vacancies, which promotes the formation of ferromagnetic order within one-dimensional nickel chains. The unusual electronic instabilities in the nickel-based Haldane system may offer new possibilities towards unconventional physical and chemical properties from quantum interactions.

Photothermal therapy (PTT) has emerged as a promising approach for treating bacterial infections. However, achieving a high photothermal conversion efficiency (PCE) of photothermal agents (PTAs) remains a challenge. Such a problem is usually compensated by the use of a high-intensity laser, which inevitably causes tissue damage. Here, we present a universal strategy to enhance PCE by regulating the molecular aggregation states of PTAs within thermoresponsive nanogels. We demonstrate the effectiveness of this approach using aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ) PTAs, showing significant enhancements in PCE without the need for intricate molecular modifications. Notably, the highest PCEs reach up to 80.9% and 64.4% for AIE-NG and ACQ-NG, respectively, which are nearly 2-fold of their self-aggregate counterparts. Moreover, we elucidate the mechanism underlying PCE enhancement, highlighting the role of strong intermolecular π-π interactions facilitated by nanogel-induced volume contraction. Furthermore, we validate the safety and efficacy of this strategy in in vitro and in vivo models of bacterial infections at safe laser power densities, demonstrating its potential for clinical translation. Our findings offer a straightforward, universal, and versatile method to improve PTT outcomes while minimizing cytotoxicity, paving the way for enhanced treatment of bacterial infections with safe PTT protocols.

This work aimed to alleviate the limitations of existing mid-infrared nonlinear-optics (MIR-NLO) crystals by conducting theoretical research on 1D-[MX 2 ] ∞ (1D = one-dimensional; M = metallic element; X = anionic element) structures in relation to NLO. An analysis was conducted on the electronic structure and optical properties of six selenides (BaZnGeSe 4 , K x Ba 1- x /2 Ga 2 Se 4 , K x Ba 1- x /2 Ga y In 2- y Se 4 , K x Ba 1- x /2 In 2 Se 4 , BaZnSiSe 4 , SrZnSiSe 4 ) and three arsenides (Cs 2 SnAs 2 , Rb 2 SnAs 2 , K 2 SnAs 2 ) using first principles. Afterwards, the inherent characteristics of these 1D-[MX 2 ] ∞ chains were further examined. The calculation results suggest that the presence of internal distortion (non-centrosymmetric) and high electronegativity in M elements can greatly enhance the NLO capability of 1D-[MX 2 ] ∞ structures. Furthermore, the first-ever prediction of K 2 SnAs 2 's NLO ability has been made. Ultimately, the establishment of a theoretical structure (K 2 BaSn 2 As 4 ) provides guidance for the subsequent creation of high-performance MIR-NLO crystals., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The prosperity of chemodynamic therapy provides a new strategy for tumor treatment. However, the lack of reactive oxygen species and the specific reductive tumor microenvironment have limited the further development of chemodynamic therapy. Herein, we reported a Fe-based cyclically catalyzing double free radical system for tumor therapy by catalyzing exogenous potassium persulfate (K 2 S 2 O 8 ) and endogenous hydrogen peroxide (H 2 O 2 ). Sufficient amounts of Fe 3+ and S 2 O 8 2- were delivered to tumor sites via tumor-targeted hyaluronic acid (HA) encapsulated mesoporous silica nanoparticles (MSNs) and released under the dual stimulation of acid and hyaluronidase (HAase) in the tumor microenvironment. Fe 3+ was reduced to Fe 2+ by the reducing agents of loaded tannic acid (TA) and intracellular glutathione (GSH), and Fe 2+ was subsequently reacted with S 2 O 8 2- and endogenous H 2 O 2 to produce two types of ROS (˙OH and SO 4 - ˙), showing an excellent anti-tumor effect. This process not only supplied Fe 2+ for the catalysis of active substances, but also reduced the concentration of reduced substances in cells, which was conducive to the existence of free radicals for the efficient killing of tumor cells. Therefore, this iron-based catalysis of exogenous and exogenous active substances to realize a dual-radical oncotherapy nanosystem would provide a new perspective for chemodynamic therapy.

Significant water-related side reactions hinder the development of highly safe, low-cost aqueous zinc metal batteries (AZMBs) for grid-scale energy storage. Herein, by regulating the length of alkyl chains, we successfully adjust interstitial voids between the polymer chains of a metal soap interface between 1.48 Å (size of a zinc ion) and 4.0 Å (size of a water molecule). Therefore, water molecules are selectively "size-excluded," while smaller zinc ions are permitted to pass through. Consequently, water-related side reactions (including hydrogen evolution and corrosion) could be effectively inhibited. Furthermore, abundant zinc ion tunnels accompanied with zincophilic components facilitate the homogenization of the Zn 2+ flux, thus preventing dendrite growth. Therefore, the Zn symmetric cell shows a lifespan of approximately 10 000 cycles at 20 mA cm -2 and 1 mA h cm -2 , and the Zn//Na 5 V 12 O 32 (NVO) full cell delivers much better cycling stability with much higher capacity retention of around 93% after 2000 cycles at 2 A g -1 compared to its bare Zn counterpart (19%). This work provides valuable insights for the utilization of metal soap interfaces and regulation of their channel size between perpendicular alkyl chains to realize precise water shielding, which is not only applicable in ZMBs but also in other aqueous batteries., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In recent years, the design and synthesis of Janus hydrogels have witnessed a thriving development, overcoming the limitations of single-performance materials and expanding their potential applications in tissue engineering and regenerative medicine. Janus hydrogels, with their exceptional mechanical properties and excellent biocompatibility, have emerged as promising candidates for various biomedical applications, including tissue engineering and regenerative therapies. In this review, we present the latest progress in the synthesis of Janus hydrogels using commonly employed preparation methods. We elucidate the surface and interface interactions of these hydrogels and discuss the enhanced properties bestowed by the unique "Janus" structure in biomaterials. Additionally, we explore the applications of Janus hydrogels in facilitating regenerative therapies, such as drug delivery, wound healing, tissue engineering, and biosensing. Furthermore, we analyze the challenges and future trends associated with the utilization of Janus hydrogels in biomedical applications.

We have developed a novel Ni-catalyzed reductive cross-coupling reaction of aryl bromides and alkyl iodides via a photoactive electron donor-acceptor (EDA) complex. This photo-induced process enables the efficient construction of C(sp 2 )-C(sp 3 ) bonds in the absence of an external photocatalyst. Electronically and structurally diverse aryl bromides, as well as secondary and primary alkyl iodides could undergo this transformation smoothly. Natural product derivatives were employed successfully, and UV-vis spectroscopy was utilized to gain mechanistic insight.

The use of mixed halide perovskites in the preparation of blue light-emitting diodes (LEDs) is considered to be the most effective and direct approach. However, the introduction of chlorine (Cl) element might raise stability issues in the system and lead to low efficiency, thereby impeding the development of deep blue light-emitting diodes with high efficiency and stability. Determining the alloy concentration and the atomic distribution of bromine-chlorine (Br-Cl) mixed systems is essential for further application of deep blue light-emitting diodes. In this work, we have systematically investigated the stability of bromine-chlorine (Br-Cl) mixed alloy systems in various substitution configurations using high-throughput theoretical calculations. Based on this, we have examined the relationship between configuration stability and three aspects: the type of octahedra, the orientation of the octahedra and the Pb-X-Pb distortion angle in the configuration., Competing Interests: The authors declare no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

The anti-obesity effect of conjugated linoleic acid (CLA) has been well elucidated, but whether CLA affects fat deposition by regulating intestinal dietary fat absorption remains largely unknown. Thus, this study aimed to investigate the effects of CLA on intestinal fatty acid uptake and chylomicron formation and explore the possible underlying mechanisms. We found that CLA supplementation reduced the intestinal fat absorption in HFD (high fat diet)-fed mice accompanied by the decreased serum TG level, increased fecal lipids and decreased intestinal expression of ApoB48 and MTTP. Correspondingly, c9, t11-CLA, but not t10, c12-CLA induced the reduction of fatty acid uptake and TG content in PA (palmitic acid)-treated MODE-K cells. In the mechanism of fatty acid uptake, c9, t11-CLA inhibited the binding of CD36 with palmitoyltransferase DHHC7, thus leading to the decreases of CD36 palmitoylation level and localization on the cell membrane of the PA-treated MODE-K cells. In the mechanism of chylomicron formation, c9, t11-CLA inhibited the formation of the CD36/FYN/LYN complex and the activation of the ERK pathway in the PA-treated MODE-K cells. In in vivo verification, CLA supplementation reduced the DHHC7-mediated total and cell membrane CD36 palmitoylation and suppressed the formation of the CD36/FYN/LYN complex and the activation of the ERK pathway in the jejunum of HFD-fed mice. Altogether, these data showed that CLA reduced intestinal fatty acid uptake and chylomicron formation in HFD-fed mice associated with the inhibition of DHHC7-mediated CD36 palmitoylation and the downstream ERK pathway.

An efficient method for the radical difunctionalization of aromatic alkynes has been developed, resulting in the synthesis of a range of valuable triarylethenes. This approach utilizes strategically designed aryldiazonium salts with tertiary alcohol substitution as bifunctional reagents, along with cost-effective cuprous chloride as a catalyst. The method demonstrates remarkable Z -selectivity and is capable of gram-scale preparation. Additionally, a novel spin-trapping reagent has been developed based on the synthesized product.

A water mediated three-component reaction of isatin, 4-aminocoumarin, and 1,3-cyclodicarbonyl compounds is reported for the synthesis of spiro[chromeno[4,3- b ]cyclopenta[ e ]pyridine-7,3'-indoline]trione and the spiro[chromeno[4,3- b ]quinoline 7,3'-indoline]trione. Up to 27 different spirooxindole derivatives were synthesized by this method. The bioactivity of these spirooxindole derivatives was evaluated and they were found to show antifungal activity against Cercospora arachidicola , Physalospora piricola , Rhizoctonia cerealis , and Fusarium moniliforme .

Hydrogen bond (H-bond) network connectivity in electric double layers (EDLs) is of paramount importance for interfacial HER/HOR electrocatalytic processes. However, it remains unclear whether the cation-specific effect on H-bond network connectivity in EDLs exists. Herein, we report simulation evidence from ab initio molecular dynamics that cations at Pt(111)/water interfaces can tune the structure and the connectivity of H-bond networks in EDLs. As the surface charge density σ becomes more negative, we show that the connectivity of the H-bond networks in EDLs of the Na + and Ca 2+ systems decreases markedly; in stark contrast, the connectivity of the H-bond networks in EDLs of the Mg 2+ system increases slightly. Further analysis revealed that the interplay between the hydration of cations and the interfacial water structure plays a key role in the connectivity of H-bond networks in EDLs. These findings highlight the key roles of cations in EDLs and electrocatalysis., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The monomeric and dimeric uranium azide complexes {[(CH 3 ) 2 NCH 2 CH 2 NP i Pr 2 ] 2 U(N 3 ) 2 } (2) and {[(CH 3 ) 2 NCH 2 CH 2 NP i Pr 2 ] 2 U(N 3 ) 2 } 2 (3) were synthesized by treating complex 1 with NaN 3 at 60 and -20 °C, respectively. A temperature-induced single-crystal to single-crystal transformation of 3 to 2 was observed. The reduction of either 2 or 3 with KC 8 yields a uranium nitride complex {[(CH 3 ) 2 NCH 2 CH 2 NP i Pr 2 ] 4 U 2 (μ-N) 2 } (4).

Artificial dissipative molecular switches based on anion recognition are of great importance to simulate biological functions and construct smart materials. Five activated carboxylic acids are used as chemical fuels for dissipative molecular switches, which consist of an imidazolium macrocyclic host and a carboxylate anionic guest. By choosing different types of chemical fuels and using varied fuel concentrations, the rates of cyclic operations are tunable. The operation is capable of undergoing at least three cycles.

Carbonyl sulfur (COS) is a prominent organic sulfur pollutant commonly found in the by-product gas generated by the steel industry. A series of Sm-doped CeO x @ZrO 2 catalysts were prepared for the hydrolysis catalytic removal of COS. The results showed that the addition of Sm resulted in the most significant enhancement of hydrolysis catalytic activity. The 3% Sm 2 O 3 -Ce-O x @ZrO 2 catalyst exhibited the highest activity, achieving a hydrolysis catalytic efficiency of 100% and H 2 S selectivity of 100% within the temperature range of 90-180 °C. The inclusion of Sm had the effect of reducing the acidity of the catalyst while increasing weak basic sites, which facilitated the adsorption and activation of COS molecules at low temperatures. Appropriate doping of Sm proved beneficial in converting active surface chemisorbed oxygen into lattice oxygen, thereby decreasing the oxidation of intermediate products and maintaining the stability of the hydrolysis reaction., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this paper., (This journal is © The Royal Society of Chemistry.)

Among all kinds of anticancer agents, small molecule drugs produce an unsatisfactory therapeutic effect due to the lack of selectivity, notorious drug resistance and side effects. Therefore, researchers have begun to pay extensive attention to macromolecular drugs with high efficacy and specificity. As a plant toxin, gelonin exerts potent antitumor activity via inhibiting intracellular protein synthesis. However, gelonin lacks a translocation domain, and thus its poor cellular uptake leads to low outcomes of antitumor response. Here, tumor acidity and matrix metalloproteinase (MMP) dual-responsive functional gelonin (Trx-PVGLIG-pHLIP-gelonin, TPpG), composed of a thioredoxin (Trx) tag, a pH low insertion peptide (pHLIP), an MMP-responsive motif PVGLIG hexapeptide and gelonin, was innovatively proposed and biologically synthesized by a gene recombination technique. TPpG exhibited good thermal and serum stability, showed MMP responsiveness and could enter tumor cells under weakly acidic conditions, especially for MMP2-overexpressing HT1080 cells. Compared to low MMP2-expressing MCF-7 cells, TPpG displayed enhanced in vitro antitumor efficacy to HT1080 cells at pH 6.5 as determined by different methods. Likewise, TPpG was much more effective in triggering cell apoptosis and inhibiting protein synthesis in HT1080 cells than in MCF-7 cells. Intriguingly, with enhanced stability and pH/MMP dual responsiveness, TPpG notably inhibited subcutaneous HT1080 xenograft growth in mice and no noticeable off-target side effect was observed. This ingeniously designed strategy aims at providing new perspectives for the development of a smart platform that can intelligently respond to a tumor microenvironment for efficient protein delivery.

Pyrroline derivatives are common in bioactive natural products and therapeutic agents. We report here a synthesis of pyrrolines and fused diaziridines by divergent radical cyclization of homoallylic diazirines, which can serve as an internal radical trap and a nitrogen source. This reaction proceeds by selective radical addition to C[double bond, length as m-dash]C or N[double bond, length as m-dash]N bonds followed by intramolecular cyclization. Frontier molecular orbital analysis provides a deep insight into the origin of the selectivity. The reaction demonstrates a new cyclization mode, broad functional group compatibility and high product diversity, and reveals a much broader chemical space for diazirine studies., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Intrinsically conductive ruthenium oxide is an excellent material for energy storage and conversion. Herein, we present hydrous RuO 2 (H-RuO 2 ) as a potent reducing agent to achieve spontaneous growth of multiple noble metals at room temperature. Self-assembled gold and platinum, comprising small-sized nanoparticles, are generated on the surface of H-RuO 2 without the need for additional templates. Structural analysis reveals that the disordered structure and the presence of oxygen vacancies trigger interfacial redox reactions between H-RuO 2 and oxidative metal salts. The resulting integrated nanostructures, consisting of a metal oxide and different metals (H-RuO 2 @metal), are subsequently used to treat inflammatory bowel diseases. In addition to biomedical applications, our developed synthetic strategy, using reactive oxides to spontaneously generate multicomponent nanostructures, also holds great significance for other catalysis-based applications., Competing Interests: The authors declare no competing interests., (This journal is © The Royal Society of Chemistry.)

Hydrogen atom transfer (HAT) and photoredox dual catalysis provides a unique opportunity in organic synthesis, enabling the direct activation of C/Si/S-H bonds. However, the activation of O-H bonds of β,γ-unsaturated oximes poses a challenge due to their relatively high redox potential, which exceeds the oxidizing capacity of most currently developed photocatalysts. We here demonstrate that the combination of HAT and photoredox catalysis allows the activation of O-H bond of β,γ-unsaturated oximes. The strategy effectively addresses the oxime's high redox potential and offers a universal pathway for iminoxyl radical formation. Leveraging the versatility of this approach, a diverse array of valuable heterocycles have been synthesized with the use of different radical acceptors. Mechanistic studies confirm a HAT process for the O-H bond activation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This paper investigates physically crosslinked organo-hydrogels for total hip replacement surgery. Current materials in artificial joints have limitations in mechanical performance and biocompatibility. To overcome these issues, a new approach based on hydrogen bonds between polyvinyl alcohol, poly(2-hydroxyethyl methacrylate), and glycerin is proposed to develop bioactive organo-hydrogels with improved mechanical properties and biocompatibility. This study analyzes local pathological characteristics, systemic toxicity, and mechanical properties of the gels. The results show that the gels possess excellent biocompatibility and mechanical strength, suggesting their potential as an alternative material for total hip replacement surgery. These findings contribute to improving patient outcomes in joint replacement procedures.

Nonadiabatic molecular dynamics simulations with a global switching algorithm have been performed at the TD-CAM-B3LYP-D3/def2-SVP level of theory for ultrafast photo-induced ring-opening and isomerization reactions upon S 1 excitation for 2,2-diphenyl-2 H -chromene (DPC). Both DPC-T and DPC-C conformers undergo ring-opening relaxation and isomerization pathways accompanied with pyran conformation conserved and converted on the S 1 or S 0 states via competition and cooperation between C-O bond dissociation and pyran inversion motions. Upon S 1 excitation, the DPC-T mainly relaxes to the T-type conical intersection region and thus yields a higher ring-opening efficiency with a faster S 1 decay and intermediate formation than those of the DPC-C mainly relaxing to C-type conical intersection. The simulated ring-opening quantum yield for DPC-T (DPC-C) is 0.91 (0.76), which is in good agreement with the experimental value of 0.7-0.9, and the thermal weight averaged lifetimes are estimated as 182.0 fs, 228.6 fs, and 1262.4 fs for the excited-state decay, intermediate formation, and ring-opening product, respectively. These time constants are in good agreement with the experimentally measured τ 1 time constant of 190-450 fs and τ 2 time constant of 1000-1800 fs. The present work could be a valuable reference for understanding the nature of the photorelaxation mechanisms of DPC, and could help to develop DPC-based photoresponsive materials.

Carotenoids in tomatoes confer significant health benefits to humans but with the disadvantage of the carotenoids from raw tomatoes not being easily absorbed for utilization. Thus, this study aimed to investigate the effects of different cooking processes on carotenoid release and human gut microbiota composition during in vitro simulated gastrointestinal digestion of tomatoes. The results showed that stir-frying significantly increased the release of lycopene and β-carotene during gastrointestinal digestion, with boiling being the second most effective treatment. The boiling-treated tomatoes enhanced the carotenoid release during in vitro fermentation. Gut microbiota analysis revealed that the digestion of the raw and boiled tomatoes promoted the growth of potentially beneficial microbiota while reducing the ratio of Firmicutes / Bacteroides , which potentially helps prevent obesity. Boiling treatment significantly reduced the growth of Peptostreptococcus and was negatively correlated with carotenoid release. Overall, the boiling-treated tomatoes were more effective than the raw or stir-fried tomatoes in terms of both colon health benefits and carotenoid release.